A meta-analysis on the influence of inflammatory bowel
disease on pregnancy
J Cornish, E Tan, J Teare, T G Teoh, R Rai, S K Clark, P P Tekkis
............................................................... ............................................................... .....
See end of article for
Dr P Tekkis, Department of
Biosurgery and Surgical
Technology, St Mary’s
Hospital, 10th Floor QEQM
Wing, Praed Street, London
W2 1NY, UK; p.tekkis@
Revised 27 September 2006
30 September 2006
Published Online First
21 December 2006
Gut 2007;56:830–837. doi: 10.1136/gut.2006.108324
Background: Inflammatory bowel disease (IBD) has a typical onset during the peak reproductive years.
Evidence of the risk of adverse pregnancy outcomes in IBD is important for the management of pregnancy to
assist in its management.
Aim: To provide a clear assessment of risk of adverse outcomes during pregnancy in women with IBD.
Design: The Medline literature was searched to identify studies reporting outcomes of pregnancy in patients with
IBD. Random-effect meta-analysis was used to compare outcomes between women with IBD and normal controls.
Patients and setting: A total of 3907 patients with IBD (Crohn’s disease 1952 (63%), ulcerative colitis 1113
(36%)) and 320 531 controls were reported in 12 studies that satisfied the inclusion criteria.
Results: For women with IBD, there was a 1.87-fold increase in incidence of prematurity (,37 weeks
gestation; 95% CI 1.52 to 2.31; p,0.001) compared with controls. The incidence of low birth weight
(,2500 g) was over twice that of normal controls (95% CI 1.38 to 3.19; p,0.001). Women with IBD were
1.5 times more likely to undergo caesarean section (95% CI 1.26 to 1.79; p,0.001), and the risk of
congenital abnormalities was found to be 2.37-fold increased (95% CI 1.47 to 3.82; p,0.001).
Conclusion: The study has shown a higher incidence of adverse pregnancy outcomes in patients with IBD.
Further studies are required to clarify which women are at higher risk, as this was not determined in the
present study. This has an effect on the management of patients with IBD during pregnancy, who should be
treated as a potentially high-risk group.
reported from a large multi-centre epidemiological study, are
10.4/100 000 and 5.6/100 000 per year, respectively.1Opinion
on the effect of IBD on pregnancy is varied, with several studies
reporting that IBD does not have an adverse effect on the
outcome of pregnancy.2–5Several population-based case–control
studies have reported no increase in still birth, neonatal death
or spontaneous abortion.6–8An association between IBD and
premature births (,37 weeks) and low-birthweight (LBW)
infants (,2500 g) has been described.6–9
Premature births result in 75% of neonatal deaths and most
neonatal intensive care admissions.10A substantial effect of
premature birth on long-term physical and mental health is
observed.11Babies born at ,28 weeks gestational age spend 85
times longer in hospital than babies born at term, representing
a considerable healthcare cost.12Even among babies born after
32 weeks, educational and behavioural problems can occur in 1
in 3 children at 7 years of age,13with 25% of children born
between 32 and 35 weeks gestational age requiring support
from non-teaching assistants at school.14
LBW is associated with poor outcomes in cognitive function,
academic achievement, behaviour and social adaptation.15 16LBW
is also associated with an increased risk of cardiovascular disease
and other chronic illnesses.17In view of the potential for adverse
pregnancy outcomes in IBD, such women should be referred
routinely as cases of high-risk , regardless of disease activity.
The present study uses meta-analytical techniques to
compare the incidence of adverse outcomes during pregnancy
in patients with IBD with that in controls.
he incidence of inflammatory bowel disease (IBD) peaks
during the reproductive years. In European countries, the
incidence rates of ulcerative colitis and Crohn’s disease,
A Medline literature search was conducted on all studies
published between 1980 and 2006 reporting comparisons of
pregnancy outcomes between women with and without IBD.
The following MESH search headings were used ‘‘inflammatory
bowel disease’’, ‘‘pregnancy’’, ‘‘outcomes’’, ‘‘ulcerative colitis’’
and ‘‘Crohn’s disease’’.
The articles were also identified using hand searching of
references and the related articles function in PubMed. No
language restrictions were observed. All of the abstracts, studies
and citations scanned were reviewed. The latest date for this
search was 18 May 2006.
Data extraction was conducted independently by JC and ET.
The following information was extracted from each study: first
author, year of publication, characteristics of the study
population, study design (prospective, retrospective or other),
inclusion and exclusion criteria, number of participants in each
group (controls, ulcerative colitis and Crohn’s disease), quality
of study, gestation, birth weight, mode of delivery, still births,
Definitions of the outcomes of interest are given in appendix A.
size for gestationalage.
We included only studies comparing patients with IBD with
normal controls, and those that reported on pregnancy
Studies in which the outcomes of comparison were not reported
or it was not possible to extract the data from the published
results and those that did not report on the pregnancy
outcomes being analysed were excluded.
Abbreviations: ASA, aminosalicylic acid; IBD, inflammatory bowel
disease; LBW, low birth weight; RPC, restorative proctocolectomy; SGA,
small for gestational age; WMD, weighted mean difference
The meta-analysis was performed in line with the recommen-
dations from the Cochrane Collaboration and the Quality of
Reporting of Meta-analyses
Statistical analysis of dichotomous variables was carried out
using odds ratio (OR) as the summary statistic, whereas
continuous variables such as birth weight or gestational age
were analysed using the weighted mean difference (WMD)20;
both were reported with 95% confidence intervals (CI). ORs
represent the odds of an adverse event occurring during
pregnancy in a patient with IBD compared with a control.
The WMD summarises the differences between the two groups
with respect to continuous variables, accounting for sample
size. For studies that presented continuous data as means and
range values, the standard deviations (SD) were calculated
using statistical algorithms and checked using ‘‘bootstrap’’
resampling techniques. Thus, all continuous data were stan-
dardised for analysis. An OR of ,1 favoured the control
population and the point estimate of the OR was considered
significant at the p,0.05 level if the 95% CI did not include the
value 1. In the tabulation of results, squares indicate the point
estimates of the effect of disease (OR, WMD), with 95% CI
indicated by horizontal bars. The diamond represents the
summary estimate from pooled studies with 95% CI.
The quality of the non-randomised studies was assessed by
using the Newcastle-Ottawa scale.21The quality of a study was
evaluated by examining patient selection methods, compar-
ability of the study groups and assessment of outcome. Studies
achieving >7 stars were considered to be higher quality.
Heterogeneity was assessed by two methods. Firstly, graphical
exploration with funnel plots was used to evaluate the
publication bias. Secondly, sensitivity analysis was undertaken
using the following subgroups: studies of higher quality, those
published in or after 2000, and those reporting on .40 patients
overall. Analysis was conducted by Review Manager V.4.2.
(QUORUM) guidelines.18 19
The literature search identified 13 studies comparing the
pregnancy outcomes of women with and without IBD. One
study was excluded from the meta-analysis as the incidence of
the outcomes of interest was not clearly reported.22The
remaining 12 studies, published between 1986 and 2005,
matched the selection criteria and were therefore included in
this meta-analysis.6–9 23–30Analysis was carried out on a total of
3907 patients with IBD and 320 531 controls. Of the 10 studies
that identified subgroups of IBD, 63% had Crohn’s disease
(n=1952) and 36% ulcerative colitis (n=1113). Table 1 shows
the study characteristics. One of the 12 studies was prospec-
tive,6with the remaining 11 being retrospective case–control
studies. Ten studies matched their patients with controls for >1
variable, with two studies not matching for any variables.8 28
Eight of the 12 studies reported on the incidence of premature
birth (,37 weeks gestation) in 1716 patients with IBD versus
298 105 controls(table 2).6 9 23–27 30Patients with IBD were more
likely to have premature infants than controls (OR 1.87; 95% CI
1.52 to 2.31; p,0.001). Analysis of patients with Crohn’s
disease versus controls7 9 23–25 29 30(OR 1.97; 95% CI 1.36 to 2.87;
p,0.001) and patients with ulcerative colitis versus con-
trols8 9 23–25 30(OR 1.34; 95% CI 1.09 to 1.64; p,0.005) also
showed significant differences in the incidence of premature
gestation. In the five studies that compared Crohn’s disease
with ulcerative colitis, there was no significant difference in the
incidence of prematurity (fig 1).9 23–25 30.
Three studies reported on the incidence of LBW (,2500 g) in
infants born to patients with IBD versus controls.6 9 26A
significant difference was observed in the incidence of LBW
in infants born to mothers with IBD (OR 2.1; 95%; CI 1.38 to
3.19; p,0.001). The incidence of LBW in ulcerative colitis8 9was
not significant, but there was a significant difference in the
incidence of LBW in infants born to mothers with Crohn’s
disease7 9(OR 2.82; 95% CI 1.42 to 5.60; p=0.003).
Mode of delivery
Six studies reported on the caesarean section rates in patients
with IBD and in controls6 24–27 30(table 2). A significant increase
was seen in the incidence of caesarean section in patients with
IBD versus controls (fig 2; OR 1.5; 95% CI 1.26 to 1.79;
p,0.001). The incidence of caesarean section in patients with
Crohn’s disease versus controls24 25 29 30was also significant (OR
1.65; 95% CI 1.19 to 2.29; p=0.003), but not in patients with
ulcerative colitis versus controls.24 25 30No significant difference
was seen between ulcerative colitis and Crohn’s disease.24 25 28 30
criteriaQuality of study
216 1, 5, 9.3
6 1, 21, 5
. 1, 2, 3, 63
1 510 7, 9 4, 5, 6
. 1, 3, 41,47
10 399.. 2, 5, 8
. 651, 3, 4, 7, 86 10
. 1, 7
3, 8 4438 1, 3, 10.
. 19521113 320 531..
CD, Crohn’s disease; IBD, inflammatory bowel disease; p, prospective cohort study; R, retrospective cohort study; UC, ulcerative colitis.
Matching: 1, maternal age; 2, infant sex; 3, parity; 4, smoking; 5, ethnic group; 6, year of delivery; 7, delivery date; 8, gestational age; 9, location; 10, gravidity.
Inclusion criteria: 1, singleton gestation; 2, most recent pregnancy; 3, histological/sigmoidoscopy diagnosis of IBD; 4, maternal age 15–45 years; 5, maternal age
>18 years; 6, inactive Crohn’s disease; 7, discharge diagnosis of UC or non-IBD; 8, pregnancies .24 weeks.
Exclusion criteria: 1, incomplete/unavailable data; 2, maternal coeliac disease, lactose intolerance or cow’s milk allergy; 3, age .60 years; 4, diagnosis of UC; 5, twin
births; 6, birth weight ,600 g or .6000 g; 7, age ,15 and .45 years; 8, uncertain IBD diagnosis; 9, medical or nursing staff; 10, active Crohn’s disease at the time
of pregnancy; 11, diagnosis of Crohn’s disease.
Influence of IBD on pregnancy 831
Small for gestational age
Four studies reported on the incidence of small for gestational age
(SGA) in patients with IBD versus controls.6 25–27No significant
difference was seen between patients with IBD and controls,
ulcerative colitis and controls,8 25Crohn’s disease and controls,25 29
and between Crohn’s disease and ulcerative colitis.24 25
Four studies reported on the incidence of still births in a group
of patients with IBD versus a control group.6 25–27No significant
difference was found in the rates of still births between patients
with IBD and controls. No significant difference was found in
the incidence of still births between patients with Crohn’s
disease and controls.7 23 30
Four studies reported on the incidence of congenital abnorm-
alities between patients with IBD and controls9 25–27and did not
show a significant difference. A significant difference was
found in the incidence of congenital abnormalities in patients
with ulcerative colitis versus controls9 25(OR 3.88; 95% CI 1.41
to 10.67; p=0.009), but not in patients with Crohn’s disease
versus controls (p=0.06).9 25 29
Higher quality studies (>7 stars)
Analysis of the higher quality studies6 7 24 25 27 29showed that
there was a significant difference between patients with IBD
and control populations in three outcomes(table 3). An increase
in the risk of premature birth (OR 1.74; 95% CI 1.14 to 2.65;
p=0.01), small for gestational age (OR 1.96; 95% CI 1.01 to
3.81; p=0.05) and the rates of caesarean section (OR 1.58; 95%
CI 1.35 to 1.84; p,0.001) was seen for patients with IBD.
Studies published in or after 2000
More recent studies were analysed, with six studies published
in or after 2000(table 3).8 24–26 28 29Results remained consistent
with the overall analysis of all studies and the high-quality
studies for the outcomes of premature birth24–26(OR 1.99; 95%
CI 1.22 to 3.26; p,0.01) and incidence of caesarean section
(OR 1.54; 95% CI 1.24 to 1.91; p,0.001). However, the later
studies did not find that the incidence of SGA was significantly
increased in the population with IBD. A significant difference
was observed in the incidence of congenital abnormalities in
patients with IBD25 26(OR 2.39; 95% CI 1.28 to 4.48; p,0.01),
which was not reported in the higher quality studies or in the
Studies reporting on >100 patients
Analysis of the studies that reported on >100 patients with
IBD6–8 23–26showed that the result was consistent with the
overall results and the analysis of later studies (table 3).
Significant differences were observed in the risk of LBW (OR
1.77; 95% CI 1.36 to 2.31; p,0.001), premature birth (OR 1.94;
95% CI 1.43 to 2.64; p,0.001), congenital abnormalities (OR
2.39; 95% CI 1.28 to 4.48; p,0.01) and the rates of caesarean
section (OR 1.55; 95% CI 1.34 to 1.79; p,0.001) in women with
IBD. No significant difference was found for the risk of SGA.
Figure 3 shows a funnel plot of the studies used in this meta-
analysis reporting on the incidence of premature birth. This is a
scatter plot showing the incidence estimated from individual
studies plotted on the horizontal axis (OR), against the standard
error (SE) of the estimate shown on the vertical axis (SE (logOR)).
None of the studies lay outside the 95% CI limits. No evidence of
publication bias or heterogeneity among the studies was seen; all
of the studies were equally distributed around the vertical axis
(p=0.23). No evidence of bias was found in the incidence of
LBW, caesarean section or congenital abnormalities.
The results of the present meta-analysis suggest that women
with IBD are more likely to experience adverse pregnancy
Pregnancy outcomes in inflammatory bowel disease versus controls
Outcome of interest
IBD (n) Controls (n)OR (95% CI)p ValueHG x2
HG p value
IBD v Control
2.10 (1.38 to 3.19)
1.87 (1.52 to 2.31)
1.87 (0.61 to 5.7)
1.48 (0.89 to 2.47)
2.37 (1.47 to 3.82)
1.50 (1.26 to 1.79)
UC v control
1.66 (048 to 5.66)
1.34 (1.09 to 1.64)
1.05 (0.51 to 2.16)
1.30 (0.86 t o1.96)
3.88 (1.41 to 10.67)
Crohn’s disease v control
2.82 (1.42 to 5.60)
1.97 (1.36 to 2.87)
1.91 (0.69 to 5.31)
5.72 (0.62 to 52.81)
1.65 (1.19 to 2.29)
2.14 (0.97 to 4.74)
Crohn’s disease v UC
1.84 (0.78 to 4.34)
0.99 (0.29 to 3.35)
1.33 (0.73 to 2.41)
HG, heterogeneity; SGA, small for gestational age; UC, ulcerative colitis.
Significant results are shown in bold.
832 Cornish, Tan, Teare, et al
outcomes, in particular premature birth, LBW and a caesarean
section. Patients with IBD were nearly twice as likely to have a
premature delivery (,37 weeks gestation) as the normal
population, a result which remained significant after the
sensitivity analysis. No significant difference was seen in
premature birth between patients with Crohn’s disease and
those with ulcerative colitis. The effect of premature delivery on
an infant’s physical, mental and social health may be
substantial,12 13 16 17and women with IBD must be aware of
the increased risk of prematurity in their babies.
The OR of a woman with IBD having an infant with LBW
(,2500 g) was 2.1 (p,0.001). This remained consistent in the
sensitivity analysis of studies reporting on >100 patients with
IBD; the outcome was not reported in the higher quality studies
or studies published after 2000. Women with Crohn’s disease
were nearly three times more likely to have an infant with LBW
(p=0.003), but not those with ulcerative colitis.
A higher rate of caesarean sections was seen in women with
IBD than in the normal population. This was corroborated in all
of the sensitivity analysis subgroups. A higher rate of caesarean
sections was seen in patients with Crohn’s disease versus
controls, but not in those with ulcerative colitis. No significant
difference was observed between ulcerative colitis and Crohn’s
disease; however, the number of patients was small. A large
study to specifically compare the mode of delivery between the
two groups is required in the future. The rationale behind the
increased number of caesarean sections in patients with IBD is
not dealt with in the studies analysed. No data exist on whether
the caesarean sections were elective or emergencies or whether
the outcomes of the infants differed after vaginal delivery and
caesarean section. Controversy exists over the most appropriate
method of delivery for patients with IBD, with some studies
reporting that the risk of incontinence and anal sphincter tears
is less in caesarean section than in vaginal delivery.31–34This is
disputed in other studies, which say that anal sphincter tears
that occur in vaginal deliveries do not affect continence35and
that vaginal delivery reduces surgical procedures and adhesion
formation in a group of high-risk patients.
p value. OR, odds ratio, CI, confidence interval.
Test for heterogeneity: x2statistic with its degrees of freedom (df) and p value. Inconsistency among results: I2test for overall effect; Z statistic with
Influence of IBD on pregnancy 833
Previous studies have suggested an association between
patients with IBD—in particular, patients with Crohn’s dis-
ease—and SGA29; however, this was not shown in this meta-
analysis. The results of the present study showed no increase in
the incidence of SGA (small for gestational age) in the population
with IBD in comparison to the normal population, or in patients
with Crohn’s disease versus ulcerative colitis. This was confirmed
in the sensitivity subgroup analysis for studies published in or
after 2000 and for studies reporting on >100 patients with IBD.
No significant difference was found in the incidence of still
births in women with IBD and the normal population. The
results of the sensitivity analysis also found no significant
differences. There have been previous reports of an association
of IBD with an increased risk of still births, although often in
No significant difference was found in the risk of congenital
abnormalities in women with IBD and the normal population;
however, a significant difference was found in the subgroup
analysis for later studies and those with larger patient groups.
The analysis of all of the studies did find a significant difference
in the risk of congenital abnormalities in patients with
ulcerative colitis versus controls, but not in patients with
Crohn’s disease. The studies that reported on congenital
abnormalities did not distinguish between the major and
minor malformations; one study included chromosomal dis-
orders,25which may result in overestimation of the risk. One
large case–control study37compared the Hungarian congenital
abnormality registry with data from the national birth registry
office. The authors reported no overall increase in the risk of
congenital abnormalities for patients with ulcerative colitis
p value. OR, odds ratio, CI, confidence interval.
Test for heterogeneity: x2statistic with its degrees of freedom (df) and p value. Inconsistency among results: I2test for overall effect: Z statistic with
834 Cornish, Tan, Teare, et al
compared with controls; however, they did report an increased
risk of selected congenital abnormalities. Further prospective
studies are required, with clarification of the type of malforma-
It is important to mention the limitations of this meta-
analysis. It would be difficult and potentially unethical to
perform a randomised controlled trial for the pregnancy
outcomes; we must therefore base our clinical decisions on
observational studies that are vulnerable to bias and confound-
ing variables. The low frequency of the adverse outcomes makes
statistical precision difficult. The studies included in the meta-
analysis did not report on disease activity in relation to adverse
outcomes. Previous studies have suggested that if a woman
conceives while her disease is active, she is more likely to have a
premature infant or one with LBW than a woman who has
quiescent disease activity.23 38The incidence of still births and
spontaneous abortions is also related to disease activity.39A
prospective study reporting on adverse outcomes and the
association with disease activity is still required. In view of
the probable increased risk of adverse pregnancy outcomes with
active disease, the management of pregnancy in patients with
IBD needs to focus on maintaining disease remission before
and during pregnancy.
A total of 19 articles have been published to date on the effect
of 5-aminosalicylic acid (5-ASA), corticosteroids, azathioprine
and anti-tumour necrosis factor a drugs (anti-TNFa) for
inflammatory bowel disease on pregnancy outcomes (table 4).
These included two prospective studies and 17 retrospective
studies on 1626 women. The results of a pooled analysis
suggested no significant increase in the incidence of still births,
ectopic pregnancies, spontaneous abortions or LBW for five
ASA group of drugs, corticosteroids, azathioprine or anti-TNFa.
An increase was seen in the number of congenital abnormal-
ities for 5-ASA, anti-TNFa and azathioprine; however, this may
Sensitivity analysis of pregnancy outcomes in subgroups with inflammatory bowel disease versus controls
Outcome of interest Studies (n)
Patients with IBD
(n) Controls (n)OR (95% CI)p ValueHG x2
HG p value
High-quality studies (>7 stars)
1.74 (1.14 to 2.65)
1.96 (1.01 to 3.81)
1.58 (1.35 to 1.84)
Studies after 2000
1.99 (1.22 to 3.26)
1.79 (0.66 to 4.82)
1.54 (1.24 to 1.91)
2.39 (1.28 to 4.48)
Group size .100
1.77 (1.36 to 2.31)
1.94 (1.43 to 2.64)
1.57 (0.64 to 3.90)
1.55 (1.34 to 1.79)
2.39 (1.28 to 4.48)
HG, heterogeneity; LBW, low birth weight; SGA, small for gestational age.
Significant results are shown in bold.
estimated from individual studies plotted on the horizontal axis (OR), against the standard error (SE) of the estimate shown on the vertical axis (SE (logOR)).
Funnel plot analysis of premature birth in patients with inflammatory bowel disease (IBD) versus controls. This is a scatter plot of the incidence
Influence of IBD on pregnancy835
relate to the increased risk for women with IBD and not drug
effects. A substantial increase was observed in the number of
therapeutic terminations for fetuses exposed to anti-TNFa
during pregnancy, with one study reporting a 19% rate of
therapeutic terminations.40Whether the reason for the termi-
nation was drug exposure or another factor is not known. This
has substantial implications if the number of adverse events in
pregnancy is not increased after exposure to the drug.
Heterogeneity was seen in some results, which we tried to
account for by sensitivity analysis. One limitation of the
sensitivity analysis is that many of the larger studies have
been published recently, and thus were in both subsets. Most of
the studies did not report on disease activity of the patients
with IBD or the drugs that the women were taking. Patients
with a higher disease activity are reported to have an increased
incidence of adverse pregnancy outcomes.23However, this
meta-analysis also has its strengths, with large numbers of
patients being analysed at once, which would have been
difficult to gather in one primary randomised controlled trial.
In conclusion, women with inflammatory bowel disease have
an increased risk, twice that of the normal population, of
having a small or premature baby. Women who have IBD are
more likely to have a caesarean section, especially those with
Crohn’s disease. The surgeon and obstetrician need to discuss
between themselves the management of delivery in women
with IBD. A definitive study is required to settle the issue of
best management and from this a new set of guidelines, to help
both patients and their clinicians determine best practice.
J Cornish, E Tan, P P Tekkis, Department of Biosurgery and Surgical
Technology, St Mary’s Hospital, Imperial College, London, UK
T G Teoh, R Rai, Academic Department of Obstetrics and Gynaecology,
Department of Urogynaecology Unit, Imperial College, St Mary’s Hospital,
J Teare, Gastroenterology Unit, St Mary’s Hospital, London, UK
S K Clark, P P Tekkis, Department of Surgery, St Mark’s Hospital, London,
Competing interests: None.
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Effect of drugs for inflammatory bowel disease on outcomes of pregnancy
Successful pregnancies, n (%)
Spontaneous abortion, n (%)
Elective termination, n (%)
Still births, n (%)
LBW, n (%)
Premature birth, n (%)
Ectopic pregnancy, n (%)
Major congenital defect, n (%)
39 47 48 56
ASA, aminosalicylic acid; LBW, low birth weight; TNF, tumour necrosis factor.
Effect of drugs for inflammatory bowel disease on pregnancy outcomes
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OUTCOMES OF INTEREST AND DEFINITIONS
Premature birth: ,37 weeks gestation.6 23–25 27
Birth weight: low birth weight (LBW) was defined as
,2500 g and very low birth weight (VLBW) as ,1500 g.6 24 25 27
Size for gestational age: birth weight ,10th centile of the
gestational age.26 29
Incidence of congenital abnormalities: diseases existing at
birth and often before birth, or that develop during the first
month of life (infant, newborn, diseases), regardless of
causation. Of these diseases, those characterised by structural
deformities are termed abnormalities.
Still births: babies born dead in the last 12 weeks of
Perinatal mortality: number of still births and deaths in the
first week.7 8
Mode of delivery: vaginal delivery, caesarean section, forceps
and vacuum delivery.
EDITOR’S QUIZ: GI SNAPSHOT ............................................................... .......
From question on page 814
On endoscopy, there was a dark purplish bulging mucosa over the mid-to-distal oesophagus with
a linear mucosal ulceration around it. Chest CT scan disclosed a hyperdense long segmental
submucosal lesion extending from the carina to the oesophageal–gastric junction (figs 2 and 3,
arrows). The diagnosis was oesophageal intramural haematoma (EIH).
EIH is a rare form of oesophageal injury. Patients usually present with a sudden onset of
retrosternal chest pain, back pain, haematemesis, dysphagia or odynophagia. The disorder can
occur spontaneously following forceful vomiting, or it can be secondary to variceal injection
therapy, oesophageal dilatation, food impaction, improper swallowing of tablets or coagulo-
pathy. Endoscopically, the lesion is described as a purplish, submucosal mass occupying most of
the lumen. CT scan typically shows a hyperdense mass within the oesophageal wall, which aids
in the differentiation of the haematoma from aortic dissection or oesophageal rupture. EIH
usually carries a good prognosis and most patients have complete resolution of symptoms in 2–
3 weeks with conservative treatment. Endoscopic therapy or surgical intervention are reserved
for those with worsening symptoms such as airway compression.
A passed fish bone was presumed to have caused EIH in the present case. This patient’s
symptoms improved after 2 days of conservative treatment, and she resumed oral intake on the
3rd hospital day. She was discharged and had no sequelae in the following year.
Influence of IBD on pregnancy837